Look at this beautiful picture and try not to think of it only as a portrait of our granddaughter.

Anna is 2 1/2 and like all little girls that age is beautiful, charming  smart as a whip, of courseand a handful-and-a-half.

Once, when she allowed as how she did not really feel like going to sleep at night, her father (my stepson Dan) asked her what she would do when he, mommy and big brother Max were asleep.

"Bad things," Anna replied immediately.

"Like what?" Dan asked.

"Stand up on the counter and get lollipops," Anna said matter-of-factly.

(Better make that two handfuls.)

With such an impish soul contained in such a cute package, Dan had tried repeatedly to make a good portrait of his daughter at this never-to-be-repeated age. He had a good toola Canon PowerShot A20 that I'd recommended to him before an overseas business trip  but this really is a snapshot camera and is not designed for real, much less close-up, portraiture.

So Dan followed the only smart path  he enlisted his mom (and my wife) Judy to make the money shot of Anna.

Judy, who was one of the best children's photographers in town, made this shot shortly before the holidays. The picture, and the circumstances surrounding it, offer a textbook lesson in successful kid portraiture.

Though made with some specialized equipment, Anna's portrait really was deceptively simple to get. It also confirms our belief that technique often is more important than gear. Judy worked with only one camera, one lens, and one film. She shot only by available window light. The portrait session lasted less than ten minutes  about as long as anyone can expect to work with babies and toddlers and get good results.

Judy's camera was a Nikon N90  her "available light camera" when we shoot weddings. [Her regular "flash camera" is a much newer Nikon F-100 on a Stroboframe flash bracket.]

The lens, arguably the most important element of this portrait equation, was a Nikkor f.4 to 5.6 70-210mm zoom.

Film was Ilford's superb Delta 3200 bxw, a film so versatile that, depending on the job and your desires, it can be shot at ISO's of 800-6400 for different effects: from surprisingly tight grain to gritty and graphic.

In this case  trying to capture a toddler in mid-toddle  Judy shot at 3200. This offered two benefits:

First, the higher ISO allowed Judy to shoot at a reasonably fast shutter speed to freeze the subject (See, for example, the sharpness in Anna's eyelashes.)

Second, the fast shutter speed required Judy to shoot with her lens almost wide open. And a wide aperture is vital in order for a picture like this to work.

A lens opened close to or at maximum aperture is going to have a very shallow depth of field, or area of apparent focus. This, in turn, means that you will blur out your background almost totally and thereby concentrate your viewer's attention solely on the subject: in this case a cute 2 1/2-year-old.

Moreover, using the 70-210mm lens at maximum zoom for a close subject all but guarantees a blurry background as well because, used like this  wide aperture and maximum zoom  the lens produces a very shallow depth of focus.

Though similar in effect, depth of field and depth of focus are not interchangeable terms. Depth of focus refers to the much narrower plane of critical focus for a specific lens-to-subject distance. With telephotos, the longer the lens, the shallower the depth of focus becomes. [This also occurs when working ultra-close, with macro lenses, but this is not what I'm describing here.]

The final element that makes Anna's portrait so beautiful is the quality of light. Window light may be the perfect portrait light. Diffuse and therefore gentle, it most often hits a subject obliquely (i.e.: from the side) thereby creating pleasant "modeling" and transition from light to dark. That's what is happening so spectacularly in this picture.

To meter for this kind of photograph, one could make a spotmeter reading of the darkest and lightest areas of Anna's face, average them, and bracket exposures on either side to be absolutely certain of at least one or two perfect exposures. As a practical matter however  and since she was working without a spotmeter and with a fidgety toddler  Judy simply used her in-camera meter to read for the shadows, and stuck to that exposure throughout.

Remember: any print film, color or black and white, is far more forgiving as to exposure than slide film. Frankly, in this case, the spotmeter regimen I described above, especially the bracketing, would have been a waste of valuable time that could better have been used to make photographs.

For this session both Anna and Judy are on our living room sofa. Anna is looking out the window and Judy is sitting to Anna's right. Since neither a parent nor (in my case) a grandparent was present to make Anna laugh or otherwise react, Judy is relying on the child's natural curiosity to create an engaging expression. Though Anna was interested in what was happening outside, she was more interested in the cord for the window shades, and like most kids she loved being able to pull on the cord to make the shades move.

But in the outtake from the portrait session, shown below the final version, see how the cord detracts from the picture. See, too, how much stronger the photograph becomes when Judy zooms in to concentrate only on Anna's face.

Throughout the brief portrait session, Judy kept up a conversation with her granddaughter, but let her do her thing without direction. In fact Judy notes that when working alone with children (i.e.: without a helper trying to amuse the subject) "the most important thing is simply to watch what the child is doing." This is easier said than done, but after years as a children's photographer, Judy has the knack of anticipating a great expression.

Every so often you might be able to tell a child: "Look over here," or "Can you smile for me?" But for every keeper you may get, you'll waste film on puzzled, bored or forced expressions.

Better to let kids be kids and photographers be photographers.

Frank Van Riper is a Washington-based commercial and documentary photographer and author. His latest book is Talking Photography (Allworth Press), a collection of his Washington Post columns and other photography writing over the past decade. He can be reached through his website www.GVRphoto.com.